556
FXUS64 KJAN 011828 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1228 PM CST Mon Dec 1 2025

...New DISCUSSION...

.KEY MESSAGES...

  - Widespread rain is expected through tonight, and this will be
    followed by cold and dry conditions Tuesday and Tuesday night.

  - It will remain colder than normal through the remainder of
    the week with additional rain events Wednesday evening through
    early Saturday.

&&

.MESOSCALE UPDATE...
Issued at 956 AM CST Mon Dec 1 2025

Rest of this Afternoon...A disturbance embedded in west southwest
flow aloft will begin lifting northeast through the Lower
Mississippi River Valley today.  As this happens, moisture currently
in the form of widespread cloud cover across the region associated
with it, will overspread the forecast area.  As this moisture
steadily overruns the drier air currently in place over the region,
light rain will eventually begin falling and will likewise
overspread the CWA during the course of the afternoon. Essentially
this, along with continued cold air over region will yield a chilly
wet afternoon across the forecast area as highs range from the upper
30s across the Delta to around 60 across the Pine Belt.

The overall forecast is in good shape.  Other than a few minor
adjustments to hourly elements of the forecast based on trends, no
major changes will be made on this morning`s update. /19/

&&

.DISCUSSION...
Issued at 1228 PM CST Mon Dec 1 2025

Tonight through next weekend...

Tonight: Synoptic/water vapor analysis consist of quasi zonal flow
migrating to southwesterly, with trough axis digging into the Four
Corners this morning. At the surface, 1031-1034mb surface high is
sprawled across the OH Valley, with northerly winds on the northern
side of the front across the north-central Gulf. Lows will be
seasonably cold tonight, some 5F to 8F along and southeast of the
Natchez Trace while 9F to 12F below to the northwest. Strong spoke
of energy/positive vorticity advection (PVA) will be swinging across
the Red River Valley area into the Ozarks to Mid South into tonight,
leading to widespread rain coverage and a sharp temperature gradient
from northwest to southeast (27F to 32F northwest of the Natchez
Trace while 33F to 43F to the southeast). As the strong ascent moves
in, drier air will overtake the region, leading to isentropic
subsidence and drying and rain chances decreasing from northwest to
southeast starting around midnight and gone by daybreak. There
shouldn`t be enough overlap for concerns for light freezing rain.
Based on recent convective allowing guidance (CAMs),
including the HREF freezing rain accumulation model (FRAM), indicate
a sharp cutoff in ice accumulation potential to the northwest of the
region. Based on that, we are going to drop the HWO graphic and
state graphic for this potential. Relevant portion of previous long
term discussion is below. /DC/

Tuesday through next weekend...

Tuesday through Wednesday night: This period looks drier and
quite cold, especially Tuesday when blustery north-northwest wind
behind the departing system will make for very uncomfortable
conditions in strong cold advection. Temperatures should struggle
to rise much above 40 F Tuesday afternoon, and some locations may
struggle to even reach 40 F along the Hwy 82 corridor. Clearing
skies and diminishing wind under high pressure Tuesday night
should allow temperatures to fall well into the 20s for most of
the area, then modification of the airmass will allow temperatures
to rebound a good bit by Wednesday afternoon under mostly sunny
skies.

Thursday through Sunday: The next significant shortwave trough
will most likely approach Thursday resulting in the development of
another frontal wave with increased warm advection over the
forecast area. Forecast confidence has increased some regarding
the potential for a couple of rounds of moderate to locally
rainfall in the Thu-Fri time frame. The storm system track should
be suppressed to near the coast, and therefore any severe weather
potential should be mostly south of the forecast area in the
continued chilly airmass. On the northern side of the system,
we`ll need to monitor for additional light freezing rain threats
due to the influx of fresh polar air. Otherwise, drier conditions
are mostly likely to return for the weekend with seasonably cool
temperatures. /EC/DC/

&&

.AVIATION...
(18Z TAFS)
Issued at 1135 AM CST Mon Dec 1 2025

Flight categories will gradually deteriorate at all area TAF
sites through the afternoon and evening as both low stratus and
eventually light rain set in across the region. Categories
currently look to remain at mainly IFR levels tonight into Tuesday
morning, with most sites recovering to at least MVFR status by
18Z Tuesday. Winds this afternoon will maintain an easterly
component between 3-8 knots, but they`ll become breezy from the
northwest overnight into early Tuesday as a surface low pressure
system develops and lifts northeast across the area. /19/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       32  47  26  57 /  90   0   0   0
Meridian      35  47  24  56 / 100  10   0   0
Vicksburg     32  46  26  57 /  90   0   0   0
Hattiesburg   42  53  29  60 / 100  10   0   0
Natchez       32  47  27  59 / 100   0   0   0
Greenville    30  42  27  51 /  90   0   0   0
Greenwood     30  43  24  54 / 100   0   0   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&

$$

19/DC/EC